1. Field of the Invention
The present invention relates generally to a system for the testing and evaluation of the situational awareness competencies and capabilities of drivers. In particular, the system is directed to testing and evaluating whether drivers exhibit minimum levels of visual detection and perception of moving as well as stationary targets and attentional/decision-making capability to remain competent in operating a vehicle.
2. Description of the Prior Art
Currently, when individuals apply for drivers' licenses, the testing of such individuals for their competency in operating a vehicle is generally limited to a written test, a summary vision test and a road test. As one would expect, the written test evaluates one's knowledge of the regulation and the established "rules-of-the-road." Conventional vision tests used by drivers testing agencies are typically limited to verifying an individual's static acuity and depth perception. When applicable, road tests under the supervision of a police officer or an examining official are used to check the individual's basic competence in maneuvering a vehicle and use of established conventions in operating the vehicle in traffic (e.g., using a signal when turning, following road signs.
However, there exists no system today that uses a standardized, objective procedure to test an individual's visual detection and perception of moving as well as stationary targets and attentional/decision-making capability in order to evaluate their situational awareness and responsiveness. As is well known, when driving, individuals are constantly bombarded by sensory inputs from the surrounding environment. The view of the road on which the individual is traveling, the sight of traffic lights and road signs, the readings on the instrument panel, the output of a radio, the temperature inside and outside the vehicle, the sound of the engine, the noise of other cars and pedestrians, conversation within the vehicle, etc. all contribute to the barrage of information that the driver must process and evaluate while operating the vehicle. Such sensory inputs do not even include unexpected occurrences such as another vehicle suddenly stopping, changing lanes or turning, pedestrians or animals stepping out in front of moving vehicles, and unnoticed road hazards (e.g., slick or icy patches on the road). Clearly, in order to operate the vehicle safely and successfully negotiate both common driving situations, unexpected hazards, the driver must have a sufficient level of situational awareness to understand the current circumstances and react accordingly. Generally, most licensed drivers possess what would be considered minimally acceptable levels of situational awareness.
Studies have shown that situational awareness, as described herein, is lowest among novice drivers, and also diminishes with age. Such declines in situational awareness stem from age-related declines in spatial vision, including static and dynamic acuity, and high-frequency spatial contrast sensitivity have been found to cause elderly individuals to experience delays in recognizing intersection features such as pavement width transitions, channelized turning lanes, island and median features across an intersection and non-reflectorized raised elements. Such individuals also experience delays in their comprehension of pavement markings and traffic signs, whereby information vital to the early stages of an individual's operation of a vehicle is, in effect, lost. When combined with attentional and decision making deficits that have been shown to increase with age, this loss of information is compounded resulting in a considerable slowdown in the driver's responsiveness. In other words, a decline in an individual's "useful field of view," selective attention and divided attention/attention switching capabilities will delay that individual's response to such situations as a change in heading or changing lanes for either avoiding a hazard or for accomplishing a desired maneuver. Such slowdowns in an individual's responsiveness are especially taxed when approaching intersections where the serial processing demands for conflict avoidance and compliance with traffic control messages and conventions increase.
Other factors that may affect the abilities of elderly individuals to effectively operate a vehicle include age-related degradations in working memory processing, and in judging distances and spatial positions. For example, a less efficient working memory process may translate into heightened degrees of risk for an elderly individual at intersections that either are geometrically complex or unfamiliar, whereby the individual having to search for and recognize navigational cues will disproportionately overburden that individual's current attention to lane-keeping and conflict avoidance. A diminished capacity to judge distances, such as the "least safe gap" ahead of oncoming vehicles, may result in the individual executing inappropriate maneuvers. Simple reaction time, while found not to be significantly slower for older drivers responding to expected stimuli under normal operating conditions, may suffer at operationally significant levels as the number and complexity of responses required to cope with unexpected stimuli (i.e., emergency situations) increases.
As a consequence, there exists a growing need to identify and evaluate the situational awareness capabilities of all those who operate vehicles on the road. This is especially important for the ever-growing population of elderly drivers, as well as novice drivers whose visual and perceptual skills suffer from lack of experience in operating a vehicle. The identification and evaluation of such persons would then aid in the process of developing countermeasures or improvements in our transportation system to compensate for such deficiencies, or mechanisms or procedures to limit or graduate the licensing of such individuals to conditions/circumstances in which their deficiencies will not be overburdened or contribute to any unacceptable hazards.
As noted earlier, there does not exist any non-driving system (i.e., excluding on-road tests) currently in use by which the full spectrum of factors that make up the situational awareness capabilities of individuals are effectively tested. Rather, current non-driving testing systems are generally limited to testing static visual acuity and depth perception. Other systems that may test for factors or abilities that are relevant to situational awareness in a driving environment are not designed or intended to test those factors or abilities in a driving application or simulation.
A need exists, therefore, for a system that effectively measures the situational awareness capabilities of individuals licensed or in the process of being licensed to operate a motor vehicle, without the exposure to risk of on-road testing unless specially warranted by diminished capabilities revealed in the non-driving testing system.
In particular, there exists a need for a system that measurably analyzes and evaluates the static and dynamic visual acuities, the static and dynamic visual contrast sensitivities, the angular motion sensitivity, the useful field of view, the divided attention and the attention switching abilities of individual drivers. That need is especially great for testing the growing elderly population, as well as novice drivers whose inexperience could compromise their ability to operate a vehicle safely.